MOEPHOLOGY AND EVOLUTION
so this is a point of value for distinguishing the Orang from the Gibbons on the one hand, and from the African Simiidse on the other.
The skin is brownish in colour, the hue varying considerably with age, sex and locality. It is, consequently, of little value for taxonomic purposes. Its intensity depends partly on climatic and partly on endocrine factors. It is never so dark as that in the Gibbons.
It is interesting to note that the two Asiatic Anthropoids differ from one another in the characters of the hair and in the pigmentation of the skin; and the African Apes also differ from one another in these features. Moreover, the histological characters of the hairs of the former differ from those of the latter.
Habits.*—The Orang is the least interesting of the Apes. It lacks the grace and agility of the Gibbons, the intelligence of the Chimpanzee and the brutality of the Gorilla. It is both wild and shy, and although its strength is immense, it attempts to escape rather than defend itself when it is attacked by Man.
Its habits agree in many points with those of the Koala, Sloths and Lorises, for they are characterized by great sluggishness. If the animal is undisturbed it will remain in the same tree for several days. When seated among the branches it appears dull and apathetic; its back is arched, its head is bowed and its long arms either hold on to a branch or hang down by its sides. Like the Sloth it is very tenacious of life, and Wallace records that he found one still alive after a fall from a tree when " both legs had been broken, its hip-joints and the root of the
* Descriptions of the habits are contained in papers 250,256, 268, 371, 282, 283, 293, 294,